(Very) Hard AND nice puzzles
The following list contains portal puzzles that have been rated as nice or very nice and that are difficult. These puzzles are recommended for experts - and allow some time to solve.
| Description | solved | Rating | |
|---|---|---|---|
 | Double negative by filuta (on 26. January 2025, 12:28) | 21 |  100 % |
| did you say walkies!? by aqjhs (on 27. June 2025, 09:27) | 24 | 99 % |
| Schadenfreude by Andrewsarchus (on 11. September 2025, 23:51) | 21 | 100 % |
| A-Row & Z-Row by Scojo (on 25. October 2025, 02:22) | 21 | 99 % |
| Pencil puzzle sudoku hybrid series #5 - Slitherlink killer sudoku by Aspartagcus (on 9. January 2021, 14:48) | 32 | 96 % |
| Les Flèches by Joseph nehme (on 15. May 2021, 07:16) | 28 | 90 % |
| Japanese Nurikabe (1) by KNT (on 4. September 2022, 05:44) | 61 | 97 % |
| Chaos Construction: Killer Cages by KNT (on 4. April 2022, 23:31) | 128 | 96 % |
| Adventskalender 2023, Türchen 16 - Untergrundangeln by Zzzyxas (on 16. December 2023, 07:00) | 33 | 98 % |
| XY-Differences III by glum_hippo (on 14. July 2020, 02:12) | 49 | 91 % |
| The Snake Nest by matt383 (on 9. October 2020, 14:03) | 40 | 98 % |
| The Corners Are Even - Arrow Odd/Even Sudoku by Mr.Menace (on 2. February 2022, 23:04) | 39 | 96 % |
| Quincies by lerroyy (on 11. June 2023, 19:14) | 39 | 92 % |
| Nothing to see here by fritzdis (on 31. August 2023, 09:36) | 35 | 98 % |
| Faultline (Filloku #4) by mormagli (on 12. October 2023, 20:15) | 38 | 97 % |
| A Little Mouthful (Short Sandwiches Sudoku) by Qodec (on 17. January 2025, 23:01) | 37 | 95 % |
| Killer Sudoku - Dirty Tricks by DiMono (on 25. November 2020, 16:27) | 50 | 97 % |
| Fill-a-Renban by SSG (on 23. July 2023, 07:22) | 43 | 95 % |
| Zeta's Nightmare by zetamath (on 15. October 2021, 15:42) | 51 | 97 % |
| The Moving Finger (Numbered Regions Chaos Construction) by tallcat (on 27. February 2025, 03:00) | 158 | 98 % |
